72 HOW SEEDS COME UP 



have reached the surface with very little disturbance of 

 the soil. In jar No. 2, the radish plantlets seem to have 

 had a harder time in coming up. Their clumsy seed 

 leaves have lifted and moved the soil in places, and left it 

 in slight ridges. 



The Pea Plantlets. The pea plantlets, in jar No. 3, 

 seem to have behaved more like those of the wheat. 

 Each appears first as a slender stem to which tiny leaves 

 are attached, and this stem seems to have found its way 

 among the soil psjticles without moving them much. 

 There are no thick, clumsy seed leaves, as in the radish, 

 although its stem is much thicker than that of the wheat 

 and quite different from it in appearance. 



The Bean Plantlets The plantlets of the bean seem 

 to have had the hardest time of all in reaching the sur- 

 face. Instead of sending up slender steins, like the peas, 

 or thin blades, like the wheat, the now greatly swollen 

 beans seem to have been lifted bodily out of the soil, while 

 the earth was lifted to make way for them. The plant- 

 'lets seem to have come up back foremost, with the tops 

 pointing downward and the beans seem to have divided 

 into halves. A little later the stems straighten up and 

 the halves spread apart, each half becoming a very clumsy 

 seed leaf, a little like that of the radish, but much larger. 



Two Types. The different ways in which these plant- 

 lets reached the surface illustrate two types. The wheat 

 and pea belong to one type, in which the plantlet grows 

 directly upward, without being hindered by clumsy seed 

 leaves. The seeds of such plants may be rather deeply 

 planted, and still their stems will be able to reach the 

 surface. The radish and bean belong to the other type, 



